Incendiary bomb



July 26, 1949.

P. N. GILLON mcmmmmr BOMB Filed March 13, 1945 JDVUWM Paul NJSillmn Patented July 26, 1949 I UNITED STATES ATENT ()F'Fi-C;

(Granted under the act of ,March .3, 1883, as amended April 30, 1928.; 3'70 0- G. 757') 4 Slainis.

The invention described herein may be manu fractured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to incendiary bombs, an more particularly to a bomb adapted to lay down a pattern of incendiary elements substantially concentric with the point of impact of a demolition bomb.

A main object of this invention is to provide an incendiary bomb having desired ballistic characteristics so that a close approximation of a concentric incendiary pattern may be-obtaincdwith respect to a demolition bomb dropped immediately preceding the incendiary bomb. 7

A further object of this invention is to provide a main incendiary bomb containing clusters: of small incendiary bombs, said main incendiary bomb being adapted to disintegrate .at an optimum distance above the target and to disperse the small incendiary bombs to provide maximum effectiveness of said small incendiary bombs as they land around the point of explosion of the demolition bomb.

Further objects of the invention. will'booome apparent from the following. description :and claims, and from the accompanying drawings, wherein:

Figure 1 is a longitudinal cross-sectional view of an incendiary bomb in accordance with this invention.

Figure '2 is an enlarged cross-sectional view taken on line 2-2 of Figure 1.

In the prior art, the dropping of the demolition bomb is followed at a definite :time interval ib'y a cluster of incendiaries with the hope that the center of impact of the incendiary cluster be substantially coincident with the point .of impact of the demolition bomb and iurther that the dispersion of the cluster will result in a reasonably satisfactory incendiary pattern. From the altitudes from which the bombs are dropped, it is almost .futile to hope that these objectives will be achieved since the disintegration of :thc icinster plus the very random ballistic characteristics 30f the incendiary bombs themselves result in .a beterogeneous flight pattern wholly .subiect to the many sources of deviation inherent inthe va ying meteorological conditions "which may zex-istcat the time and place at which the bombs are dropped, and the unpredictable efiectthereof (on small incendiary missiles which are inherently very inefiicient ballistically.

Incendiary bombs, as their name implies, are used to spread destruction by, fire, .andare gen 2 orally used in association with demolition bombs. The destructive effect of the demolition some upon impact is produced by the violence of the detonation. The incendiary bombs, small and hexagonal in shape, are arranged inclusters and dropped from the plane as a unit, c ming apart in, the air to arm and fall separately to cover the area of destruction .of the demolition bomb and complete by fire the destru tion ori inated by the said bomb. There is, of course, taotiaal necessity of obtaining awn-incendiary pat e n onoentric with the point of impac of the demolition bombii the incendiary is to be efiectivc arry.- ing out this function.

The incendiary clusters thrown from th plans were not stable, and did not have, or .even approach the ballistic .efliciency of the demolition bomb. There was no way of adjusting the pate torn, and the bombing plane had not only to remain over the target, but was often required .to repeat the run on a lower level at .a greatly increased hazard, due to the usual increase anti-aircraft fire atter the dropping of demolition ,bombs, in order to obtain even a minimum n.- .oentration of the incendiaries. This old method was not susceptible of material improvement even this addedzeffort and risk. -I ,felt that the cluster was encased in alsheli or body to form abomb which might bedropped irom the plane in the same manneras the demolition bomb, and which would permit me of ballistic ooeijdcien ts and aiming sights, the exa t {time lag required between the dropping of the two bombs mi ht be readily determined and a r as na le apnr xima .ti-on of the ,ooncentrio patte n obtained, so that he .oenter-of impact of the i nd-ia'ry cluster would be sensibly coincident with the point .of contact of the-demolition bomb- It is a p ime p pose of this inven ion to achieve the desired obiectivesby housin th incendiary bombs in asheath or body of relatively brittle material, such as plastic or the iike, and in snob a manner that ballistic charaoteristios .difie in only s igh l and in a known manner from thos of the demolition bomb with which th imend ary bombs are to be dropped are ob ained.

By dropping the incend aries hous as above described after apredetermined time lag respect to the droppin f. the demol t on bomb.- andby providing means :f r disintegrat ng the sheathbr body at an ioptimumdistan o above {th a a very reasonable appr ximat n (of the desirednoncentric pattern may be achieved. ithe optimum distance selected may b such that eX- plosion of .the demolitionibomb will have subsided atively brittle material adapted to be readily dis- 7 integrated. The nose portion l3 of housing la is provided with a fuze 4 of a type adapted to be set for explosion at a predetermined altitude above the ground.

A rearwardly tapered metal tail section l0 supporting a tail fin assembly H, to complete the bomb and stabilize its'flight, is secured to said housing la in any suitable manner, such as riveting, as at I2. Suspension lugs I4 for use in Army bomb'racks, or a single suspension lug l5 for similar Navy use, or both, are secured to housing lot by riveting or otherwise. The group of incendiary bombs 2 are secured within the housing Ia. by pressure of the Walls of said housing, as shown in Figure 2, and are restrained from longitudinal translative movement relative to the said housing by the tapered nose and tail portions l3 and II], respectively.

The numeral 5 designates a metallic burster tube disposed axially in the housing la within the group of small incendiary bombs 2 containing an explosive charge 6 of any suitable explosive, which upon ignition and explosion will cause the tube 5 to expand and push out the bombs 2 after shattering of the housin la and the frangible bands 3 by the pressure set up Within the said tube. A collar 1 is provided for securing the forward end of said tube 5 to the fuze 4 to form a continuous flame passage through which the flame from the burning primer withinthe said fuze may communicate with the explosive 6 to explode it. The rear end of tube 5 is supported in a socket 8 in a base plug 5 of the tail portion Ill. The said tube 5 also cooperates with the housing la in supporting the group'of small bombs within the said housing.

The ballistic characteristic of the assemble incendiary bomb are thus brought close to those of demolition bomb, and being known in relation to the ballistic characteristics of a demolition bomb, said incendiary bomb may be dropped at an accurately timed interval after dropping the demolition bomb so that the incendiary pattern will be concentric with the point of explosion of the demolition bomb.

Fuse 4 is preset for explosion at a predetermined height above the ground, said height being sufficient to secure proper dispersion of the small incendiary bombs resulting from the explosion of fuse 4 to provide a satisfactory incendiary pattern around the point of explosion of the demolition bomb. The fuze is not limited to any particular type, but may be a time fuze, a barometric pressure fuze, a proximity fuze, or any other fuze adapted to be set to function at a predeterminable elevation relative to the earth, as occasion may demand. The fuse has its nonexplosive functioning elements external to the bomb body and the fuse itself is connected to the bomb body in the conventional manner. This fuse should be mounted so that its detonator or squib will flash through the continuous central channel of the burster tube 5 containing the explosive which is adjusted so that the resulting explosion will cause the said tube to expand under the pressure built up by said explosion rupture the sheath and disintegrate the clustered incendiaries. The force of the explosive pressure built up within the tube 5 is not only suificient to disintegrate housing I but will also break frangible bands 3 scatterin the small incendiary bombs 2. The force of this explosion, however, is not great enough to break up or to immediately ignite the small incendiary bombs, such ignition occurring when the small incendiary bombs land; At the time of dispersion, the incendiary bombs will be close enough to the ground so that their erratic flight characteristics ,will not substantially deflect the incendiary pattern away from satisfactory concentric relation to the point of explosion of the demolition bomb.

Since the whole objective of the invention is to correct the ballistic inefliciencies of incendiary bombs as compared with demolition bombs, I have herein disclosed an incendiary bomb whereby the'objective desired is achieved by nesting the small incendiary bombs in a shaped plastic body in such a manner that the center of gravity, longitudinal and transverse moments of inertia, and the slenderness ratio of the incendiary missile produces a ballistic coeflicient only slightly inferior to that of the demolition bomb with which it is intended to be used.

As heretofore pointed out, the disintegrating charge can be made up of any explosive especially fitted for use in a particular bomb, and in such readily determinable amount as would provide the disintegratin force necessary to accomplish the proper distribution of the incendiary cluster without breaking up any individual small bomb.- While a specific embodiment of an incendiary bomb has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope ofthe appended claims.

1 What is claimed is:

1. An incendiary bomb adapted to be released from aircraft, comprising a streamlined brittle body, a cluster of small incendiary elements nested within said body, frangible means binding said elements together to form said cluster, explosive means positioned within said cluster adapted to rupture said body and said frangible means simultaneously to scatter said incendiary elements, and a fuze carried by said body adapted to'function at a predetermined distance above the ground to explode said explosive means.

2. An incendiary bomb adapted for release from aircraft, comprising an elongated brittle body provided with a tapered nose portion, a separate rearwardly tapered tail portion attached thereto, the said tail portion being adapted to provide flight stability, a plurality of incendiary elements positioned within said body, the said elements being securely bound together to form a compact cluster by a plurality of frangible bands and restrained from longitudinal movement within the said body by the nose and tail portions thereof, a burster tube containing an explosive mounted Within said cluster to rupture said housing and said frangible bands, a fuze adapted to be set to function at a predetermined altitude above the ground mounted in the nose portion of said body and communicating with said explosive to explode the same, and means carried by said body for releasably suspending said bomb in an airplane, whereby the ballistic characteristics of said bomb may be determined with reasonable accuracy.

3. An aerial bomb for dispensing a plurality of incendiary bombs dropped from an airplane at an optimum distance above a target, comprising in combination a tapered plastic body having a tail portion, including fixed fins, to house a plurality of incendiary bombs therein, frangible 10 means securing said bombs together for positioning in said .body, a fuze adapted to be set to function at a definite point above the earth carried by said body, and explosive means within said body adapted to be exploded by said fuze, whereby the said body and said frangible means are ruptured to dispense said incendiary bombs.

4. The structure of claim 3 in which means are carried by said bomb for releasably securing said bomb in the bomb rack of an airplane.

PAUL N. GILLON.

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,283,075 Chacon Oct. 29, 1918 1,287,372 McGraW Dec. 10, 1918 2,346,494 Leland Apr. 11, 1944 FOREIGN PATENTS Number Country Date 85,741 Switzerland July 1, 1920 593,537 France May 29, 1925 850,398 France Sept. 11, 1939 699,540 Germany Dec. 2, 1940 OTHER REFERENCES Life Magazine Apr. 1, 1940, pp. 34, 35. Popular Science, March, 1943, page 115. 

